Continuous catalyst conversion processes in the petrochemical industry. The fluidized catalyst cracking of hydrocarbons is an important process for the production of lighter hydrocarbon components, and it is an important process for the production of ethylene and propylene. The fluidized catalytic cracking process continuously circulates a fluidized catalyst between a reactor and a regenerator.
Another route for the production of propylene can be obtained by the dehydrogenation of propane through catalytic dehydrogenation. The dehydrogenation catalysts generally comprise noble metal catalysts on acidic supports, such as alumina, or silica alumina, or zeolitic materials. However, the reaction is strongly endothermic, and requires a high temperature for the reaction to proceed at a satisfactory rate. At the same time, the reactions need to be controlled to limit the degradation of the propane to form methane and ethylene, and where the ethylene can be hydrogenated by the hydrogen released through the dehydrogenation of the propane. The process also leads to coking of the catalyst, and deactivates the catalyst. The catalyst therefore needs to be regenerated on a regular basis after relatively short periods of operation, or residence, in the dehydrogenation reactor.